1. Field of the Invention
The present invention relates to testers, and particularly to an input/output (I/O) port tester which can test I/O ports of electronic devices.
2. Description of related art
Generally speaking, most electronic devices have I/O ports for communicating with other external devices. Before selling these electronic devices, manufacturers need to test the I/O ports of the electronic devices.
Referring to FIG. 1, a partial circuit diagram of a conventional network monitor device is provided. The network monitor device includes twelve I/O ports 1a-12a. The I/O ports 1a-4a are serial communication ports adapted for connecting with serial communication devices such as RS485/422 communication devices. The I/O port 5a is a voltage source port for supplying power. The I/O port 6a is a water sensor port adapted for connecting with a water sensor device for testing whether moisture has penetrated the network monitor device. The I/O port 7a is a direct current (DC) sensor port for detecting a DC power source. The I/O port 8a is a ground port. The I/O ports 9a and 10a are relay ports. The I/O ports 11a and 12a are data ports for controlling external devices. Users need to use many kinds of testers to test the ports 1a-12a respectively, such as a serial communication port tester to test the I/O ports 1a-4a and a water sensor device to test the I/O port 6a, which is unduly laborious and time-consuming and inconvenient.
What is desired, therefore, is to provide an I/O port tester which can conveniently test many kinds of I/O ports of an electrical device.